Hi Guys,
i need some help here.
I am studying the following police siren: http://www.simonthenerd.com/files/policesiren/PA300.pdf
At page 16 there is the schematic. VERY old school electronics. In the specific i was focusing my attention on the LM556 part (top left corner, ICI2) which is the part that makes the air horn possible.
All i'm trying to do is to recreate that sound using a PIC (12F675). I'm really guessing the frequency used for this tone but i can't and i don't have an oscilloscope to recreate that circuit and analyze the frequency. Could anybody please give me a hint on what frequency to try and what speed?
At the moment my best attempt was to use 2 alternate frequencies (2000hz and 0hz) both at 3ms but somehow it doesn't sound how it is supposed to.
Thank you in advance
i need some help here.
I am studying the following police siren: http://www.simonthenerd.com/files/policesiren/PA300.pdf
At page 16 there is the schematic. VERY old school electronics. In the specific i was focusing my attention on the LM556 part (top left corner, ICI2) which is the part that makes the air horn possible.
All i'm trying to do is to recreate that sound using a PIC (12F675). I'm really guessing the frequency used for this tone but i can't and i don't have an oscilloscope to recreate that circuit and analyze the frequency. Could anybody please give me a hint on what frequency to try and what speed?
At the moment my best attempt was to use 2 alternate frequencies (2000hz and 0hz) both at 3ms but somehow it doesn't sound how it is supposed to.
Thank you in advance